Blepharitis is a chronic inflammation – a long-term swelling – of the eyelids and eyelash follicles. It may be caused by seborrheic dermatitis, acne, bacterial infection, allergic reaction or poor eyelid hygiene. The eyes may become red or blurry, as well as tear frequently. The eyelids crust, flake, scale or redden, and the smooth inside lining of the lids may become rough. In more serious cases, sores can form when the crusting skin is removed, the eyelashes may fall out, the eyelids can deform, the infection can spread to the cornea, and patients often suffer from excessive tearing. Blepharitis can also cause styes, chalazions and problems with the tear film.